A new study shows that ozone pollution in the western United States can be increased by La Niña, a natural weather cycle at the surface of the Pacific Ocean. Scientists have come to recognize that La Niña and its opposite phase, El Niño, affect various kinds of weather around the world; the ozone finding is first to show that it also directly affects pollution. The study appears in the current issue of the journal Nature Communications.

According to a new study, neighborhood differences in rates of childhood asthma may be explained by local levels of soot produced by trucks and residential oil burners. The study, by public-health and air-pollution scientists at Columbia University, appears

New York subway commuters may worry more about rats and rising fares than dust floating through the system, but for the workers who spend their whole shift below ground, air quality has long been a concern. Results from a new pilot study using miniaturized air samplers to look at steel dust exposure may help them breathe easier.

Working in the subway several hours each day, subway workers and transit police breathe more subway air than the typical commuter. Subway air has been shown to contain more steel dust than outdoor or other indoor air in New York City. But do transit workers’ bodies harbor elevated levels of these metals? And does this translate into a health concern for the workers?

Columbia University researchers have found that steel dust generated in the New York City subway significantly increases the total amount of airborne iron (Fe), manganese (Mn) and chromium (Cr) that riders breathe. The airborne levels of these metals associated with fine particulate matter in the subway environment were observed to be more than 100 times greater than levels observed in home indoor or outdoor settings in New York City.